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SOBRE ESTE BLOG

I'm a well-known mainframe performance guy, with almost 30 years of experience helping customers manage systems. I also dabble in lots of other technology. I've sought to widen the Performance role, incorporating aspects of infrastructural architecture.

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Many of you will have, by now, installed the Adobe AIR runtime. Most probably it will be to run something like Twhirl. At this point many of you will be asking "what's Twhirl?" If I said it was a nice desktop application that makes using Twitter so much easier I hope you don't ask "what's Twitter?" :-) So, we're beginning to see these desktop applications coded using Adobe AIR, which stands for... [More]

The same Kevin Keller I mentioned in this blog post is running a one day pilot of a "Web 2.0 and System z" workshop on July 8th, in IBM Böblingen. It's designed for customers, though some of the audience will undoubtedly be IBMers. I've looked at the agenda and, while I'm on it, it's a great agenda. :-) Actually it has the highly-acclaimed Luis Suarez on the agenda as well. (I'm looking... [More]

Take a look at my German colleague Kevin Keller's new blog in Web 2.0 and z/OS. I think you'll be pleasantly surprised at what runs on z/OS that the rest of the world would regard as modern . :-) I say "modern" rather than "Web 2.0" because I feel the latter term is generally overused. What is really to the point is quite how much stuff could (and in many cases should) be implemented on z/OS, e.g.... [More]

Hats off to Jonathan Feinberg (who's created a number of neat sites inside IBM) for creating Wordle. The above is a nice depiction of the keywords for my blog. Click on it for a bigger version. Go to here to make your own from any sets of text you like.

I'm not sure if anyone's done this before. Certainly I've not seen any results... We're beginning to write up some tests the "A Team" (Alain and Pierre) ran before their return to France. Which provides me with some test data. Fortunately I had a stab at mapping the new fields this data contains. One in particular is Stucture CPU (R744SETM)... So, I got to plotting CPU per request against request... [More]

It's fair to say I've written very little in terms of book words these past two days. That's because I've been "doing research" on how the cache structure counters really work. "Doing research" is a euphemism for "finding out how the heck the darned thing works". Which is in itself a positive thing to do - but it does rather get in the way of writing stuff. :-( There is a section in the SMF 74... [More]

I had to eat a little bit of humble pie today - because I made an elementary mistake. I'm going to share it with you - to save you making it, too. :-) And I'm very sure I'm not going to make it in a customer situation. (Residencies are great for making mistakes in a safe environment.) :-) In CFLEVEL 15 and z/OS Release 9 RMF you get a new field at the structure level: R744SETM. This is the CPU... [More]

Sometimes reading the SMF manual buys you less than you thought. I had completely ignored a nice little field - and the code I inherited to analyse SMF 74 Subtype 4 Coupling Facility data ignored it as well. R744SLEC in the Request Data Section for a structure is described by the text "Lock structure only: lock table entry characteristic". Can you guess what it is? :-) If I told you it was a one... [More]

The other three residents are busy doing extensive setup work - and we hope to have some nice measurements later on. (I'm not sure how much later on there actually is, mind.) :-) So I have no RMF or DB2 SMF to play with yet. :-( Meanwhile I'm beginning to come up to speed again after the glorious experience of recovering from moving five time zones to the west. :-) So I actually got to writing... [More]

So, I'm about to start writing. At last! As a team we had a discussion yesterday about how to deal with performance numbers. One of the roles I'm playing on the team is "the guy who writes about performance numbers". So we came to the following conclusions: We really can't talk about products made by other people - such as SAS/MXG or TMON for DB2. That's right out - because of our basic provenance... [More]

I feel like I'm on "home turf" at UKCMG... My use of English can be looser :-) and it's so nice to catch up customers with whom I've a long and (I hope) fruitful history. I did my (slightly updated) "Memory Matters" and "Much Ado About CPU" presentations - and I really do lose track of how much change there's been in each of them (though it seems to me I fiddle with them A LOT. :-) Actually I sat... [More]

I'm going to try something different this year – and composing this using OpenOffice Writer on my new ASUS EEE PC while flying home is certainly different. But what's new is not documenting all the bits and pieces I learnt. Instead I'm going to give some impressions: On Monday afternoon we had an enforced evacuation from the conference centre and much of the environs – because of a World War II... [More]

I wonder how many of you recognise the terms "READ_COCLASS", "WARM", "RFCOM","WRITE_DATALIST" and "CASTOUT_DATALIST". Granted that in that list are two pairs of terms that I believe to be synonymous, but all five are relatively recent enhancements to Parallel Sysplex infrastructure that have a positive impact on DB2 Data Sharing performance (or at least the management of Performance). As I... [More]

Tomorrow I fly to Dresden for the annual European System z Technical Conference. It's at just the time of year when I can decide in my head that Spring has sprung and that Summer won't be long coming. :-) This is a great conference and I always enjoy attending it (and presenting at it). Talking of which, I have three sessions this year: Much Ado About CPU which has a fair modicum of new stuff,... [More]

As some of you will know IBM has a twice-yearly "HackDay" programming fest. And the latest - HackDay5 - was last Friday. Couched as a competition it isn't really... It's a heck of a sight more cooperative than that. (Else I wouldn't have got involved.) I've participated in all five we've had over the past two years. And it's been great fun. This time - for the second time - I've physically gone to... [More]

We've been issued new guidance: Delete SPAM rather than mark it invisible. Disallow posting comments after, say, 30 days. The latter appears to work at the individual entry level. Three of my entries have become particularly troublesome (for some unknown reason). So I've set them to "no more comments". If you find a comment of yours bounced then please do let me know. I'm sure we can fix it.... [More]

Very few people spend as much time as I do down in the guts of individual SMF records. But for those who do ERBSCAN / ERBSHOW is an invaluable tool... ERBSCAN, issued in ISPF 3.4 against an SMF data set, presents you with a list of SMF records and some VERY high level information. Such as the date and time the record was cut, the SMF ID and the record type and subtype. ERBSHOW nnnn, issued from... [More]

Every once in a while :-) I do something really dumb... Thanks to Debra and family for the bath bomb... Rather than throw it in the bath wrapped I chose to cut it open and pour the contents in. The result? Rather like bathing with dead flies. :-) And, no, I was sober at the time. :-)

As I've mentioned before I'm using Roller's "Referer URL" page - for my developerWorks blog - to analyse where my blog hits are coming from. (It's an informal exercise because I can only really work with hits that involve a search engine of some sort - and some 80% of my hits are said to be "direct".) Recently I've had a rash of "pornospam" comments to my blog. (As previously noted I've a way of... [More]

Occasionally you'll (hopefully briefly) see SPAM comments on this blog. I'm grown up about this sort of thing and just remove the comments when I see them. I hope you're grown up enough to cope with this irritating phenomenon as well. But I've gotten fed up with having to mark these comments as SPAM. So I added some code to my Firefox extension to create a little button on my "Comment Management"... [More]

Thanks to Oliver Robinson for pointing this out to me: In MXG Newsletters Numbers 50 and 51 Barry Merrill discusses MXG / WPS support in what I think is a detailed and fair way. (Oliver, for the record, works for WPC who develop WPS.) Barry and I discussed WPS and MXG over a year ago. I think WPS has come a long way in this time and is now a very credible alternative to SAS for many applications,... [More]

Nowadays - actually thenadays :-) but more so nowadays - the value of a web page is related to how well structured it is. Well structured from a mashup programmer's point of view... As I often say you have to assume that people will want to take your web pages and mash them up in ways you never thought likely. If your web page is hard to navigate, extract material from, etc then people will use... [More]

This is really just a test of some Firefox Extension code of mine... but it's kind of interesting in its own right... The following is a table containing the country-level summary of Search URLs that somehow get a reader to my blog on any given day. (I have another table ranking search terms.) Most days the USA and India are at the top of the list. And there's usually a smattering of other... [More]

!This is a great song for a great cause... I saw Queen + Paul Rodgers play this in 2005 in Hyde Park. Actually Paul did nothing - Roger Taylor sang it. :-) But now they've worked on it as part of their current studio sessions and have rushed it out - for free . So download, play it, donate and tell your friends.... Get it from here and read all about it . Now I've Downloaded And Listened To It I... [More]

In September 1997 DFSORT Release 13 was shipped (to coincide with the release of OS/390 Release 4). It took a nice idea from Syncsort and extended it. In case you didn't know OUTFIL allows you to read an input data set (and perhaps sort it) and write to multiple output files from the resulting records - perhaps selecting subsets of the records and reformatting them (and differently to each output... [More]

!Somehow I seem to have end up writing a "Memories of..." series of blog posts. That wasn't the intention but a set of threads on IBM-MAIN Listserver got me to thinking about these nice venerable technologies - VIO, Hiperbatch, Batch LSR and Pipes. By couching these posts in terms of "memories of" it sounds like they're perhaps obsolete. With the possible exception of Hiperbatch that probably... [More]

Thanks to Kevin Aires for pointing this out to me... "Boris in Wonderland" is a chat show in Secondlife - hosted by one Boris Frampton of IBM. Go here for the first episode. Andy Stanford-Clark (Ginger Mandelbrot in Secondlife) is interviewed about his applications and creations. The Monty Python quote "look out there are Llamas" is relevant here - but you'll just have to roll the video to find... [More]